Recycling Efforts Research Articles

Compatibilization of Polymer Blends by Ionic Bonding

Chemically dissimilar polymers are rarely miscible due to a specific entropy of mixing that scales as 1/N, where N is the degree of polymerization. As a consequence, the compatibilization of immiscible polymer blends presents a major challenge to plastics recycling efforts. We demonstrate that when the chain ends of two highly immiscible polymers are functionalized with reacting acid and base groups, ionic junctions form in situ by proton transfer, leading to the stabilization of interfaces and the suppression of macroscopic phase separation. Due to the dynamic nature of proton transfer, the microstructure can be tuned via ionic bond energy (h) and segregation strength (χN). In this work, a library of ionically end-functionalized polystyrene (PS) and polydimethylsiloxane (PDMS) is used to demonstrate the importance of end-group acidity/basicity and molecular weight on compatibilization. Well-ordered lamellae result from blending polymers with strong acid and base units, while less ordered, more swollen microphases occur in systems with weak acid and base end groups or larger molar mass. Heating the ionic blends results in reverse proton transfer and destruction of the close-contact ion pairs. As a result, domains are swollen with the resulting unbonded homopolymers, which in sufficient amounts, leads to macrophase separation. Moreover, external salt ions screen the electrostatic attractions and disturb ionic compatibilization. The self-consistent field theory (SCFT) of this system reveals that the ionic interactions can be tuned to create a broad range of morphologies, from microphases to macrophases.

Utility of Deactivation By Saltwater Immersion for End-of-Life Processing of Lithium-Ion Cells

Recycling of lithium-ion batteries is envisioned to become an important aspect of ensuring future access to the critical materials used in lithium-ion batteries (LIB) (1). This is particularly true for nickel, cobalt, and lithium, which have experienced extreme price fluctuations and projections of supply shortfalls in the near future. Current recycling efforts are focused on recovering the most valuable components like those mentioned above, however emerging efforts have also demonstrated the feasibility of recovering intact active materials and even direct recycling of electrode composites. All recycling efforts have a common logistical challenge – cells and batteries must be aggregated at recycling facilities once they reach the end of their useful life. This aggregation also introduces safety challenges due to the possibility for residual or stranded energy in lithium-ion cells. A 2021 report from the United State Environmental Protection Agency (US EPA) highlighted this issue, reporting that 89% of 245 fires reported from U.S. materials recycling facilities between 2013-2020 were attributed to lithium metal or lithium-ion batteries (2). Energetic failures including thermal runaway has been reported in lithium-ion cells of various chemistries at states-of-charge (SOC) as low as 15% in response to thermal abuse, and cells experienced temperatures above 100 °C in response to external short-circuiting at SOC as low as 30% (3). Saltwater immersion has been reported as an effective method to remove residual energy from lithium-ion cells (4) (5) (6). However, most efforts have focused on the discharge rate of various solution conditions as determined by cell voltage, and offer limited insight into safety impacts and the recoverability of active materials. Qualitative descriptions of corrosion during saltwater immersion, which can be severe, have also been reported in academic literature. This presentation will focus on demonstrating the role of various immersion solution parameters (e.g. solute and other additives, temperature) on the efficacy of removing residual energy from LIB as measured by electrochemical testing of representative systems as well as commercial lithium-ion cells. Impacts of corrosion and cell safety will be discussed through materials analysis (X-ray Photoelectron Spectroscopy, Scanning Electron Microscopy + Energy Dispersive X-ray Spectroscopy) and battery calorimetry (Accelerating Rate Calorimetry). Recycling of Lithium-Ion Batteries—Current State of the Art, Circular Economy, and Next Generation Recycling. Neumann, J, et al. 2102917, 2022, Advanced Energy Materials. United States Envrionmental Protection Agency. An Analysis of Lithium-ion Battery Fires in Waste Management and Recycling. 2021. EPA 530-R-21-002. Safety of Lithium-Ion Cells and Batteries at Different States-of-Charge. Tapesh, Joshi., et al. 140547, 2020, Journal of the Electrochemical Society, Vol. 167. Pretreatment options for the recycling of spent lithium-ion batteries: A comprehensive review. Yu, D, et al. 107218, 2021, Minerals Engineering, Vol. 173. A comprehensive review on the pretreatment process in lithium-ion battery recycling. Kim, S, et al. 126329, 2021, Journal of Cleaner Production, Vol. 294. Aqueous solution discharge of cylindrical lithium-ion cells. Shaw-Stewart, J, et al. e00110, 2019, Sustainable Materials and Technologies, Vol. 22. Figure 1

PENGEMBANGAN BIOGAS SAMPAH PASAR

The traditional market has degradable waste, especially from the types of vegetables and left over food, the waste is not managed properly will potentially cause disease and poor aesthetics. There are various kinds of recycling and waste utilization efforts to reduce the potential negative impacts and produce a product that is more economically valuable so that the volume of waste does not continue to increase. Based on this consideration, it is necessary to study the generation and composition of waste as well as the potential for biogas from waste in Pasar Pagi Samarinda. The organic material of Pasar Pagi waste which is used as energy through the anaerobic digestion process can be considered from the quality of the biogas and the volume of biogas produced. The determination of waste generation and volume of waste is calculated based on the number of traders in the Pasar Pagi. The biogas production in the digester uses organic waste raw materials from Pasar Pagi and rumen liquid in a ratio of 1:1. The Calculation of gas formed was carried out using a U manometer, temperature measurements using a thermometer, pH measurements using a pH meter were carried out every day and VS measurements were carried out every seven days. The mass of Pasar Pagi waste was 1.81 kg/trader/day and for the volume unit is 4.90 L/trader/day. The total composition of organic waste for vegetables, fruit, and food waste was 85.5%, organic waste in the form of cardboard or paper waste was 2.9%, the composition of plastic waste was 10.7% and metal was 0.9%. The pH of the digester during the formation of biogas shows an acidic condition, and the increase in pH that occurs is only able to reach pH 6 or close to neutral. The temperature in the digester at the beginning of the process tends to increase, then decreases and increases again at the end of the process, but does not affect the biogas production that is still ongoing. The addition of cow rumen contents was able to increase the volume of biogas formed in organic matter and the VS value decreased every week accompanied by the increase in biogas production. This shows that the organic waste in Pasar Pagi has the potential for biogas production.

Towards zero waste in pharmacy: Challenges and opportunities in Singapore

Background In line with zero-waste movement, there is a need for pharmacies to start reducing waste. There is no systematic waste minimization efforts by local pharmacies or studies to evaluate their effectiveness. Aim Assess behavioral change factors towards waste minimization at National Cancer Centre Singapore and evaluate effectiveness of recycling effort and patient education campaign. Methods Preliminary surveys were carried out among pharmacy staff, patients/caregivers to assess behavioral change factors. Recycling rate of staff and plastic bag consumption levels of patients/caregivers were measured. Results 46 staff members and 335 patients/caregivers were surveyed. Both populations were optimistic about the suggested green initiatives, 82.6% of staff members viewed recycling as a potential solution to reduce waste and 67.6% of patients and caregivers demonstrated willingness to participate in a Bring Your Own Bag (BYOB) campaign. Recycling efforts improved recycling rates by 53.4% while BYOB campaign resulted in no notable decrease in plastic bag consumption levels. Conclusion This study revealed the need for improvements in current waste management practices in local pharmacies, and demonstrated the effectiveness of implementing a recycling effort. BYOB campaign was not shown to be effective. Follow-up studies should be carried out to capture long-term sustainability data. Future efforts should include studies at other non-specialized local pharmacies.

Shredder machine for plastic recycling: A review paper

Plastic pollution has become a global concern due to poor plastic waste disposal management. As an alternative, independent recycling efforts are necessary. A Plastic shredder machine is a preliminary machine used to cut plastic waste into small pieces before turning it into useful products. The concept design of the shredder machine that is currently available is fairly similar. The shaft and blades are the critical components in the shredder machine that determines its performance. The geometry and orientation of the blades that were fitted into the single or double-shafts were found to directly affect the shredding performance. Therefore, this article aims to review the various geometry and orientations of the blades that give direct effect on the shredding performance, as well as identifying the research gaps related to the shredder machine for plastic waste materials

Will Costliness Amplify the Signalling Strength of Past Pro-Environmental Behaviour? Exploratory Study on Autonomy.

Research has shown that the extent to which previous environmental actions are linked to people’s environmental self-identity influences subsequent environmentally-friendly behaviour. The study empirically examined the influences of recycling efforts on subsequent pro-environmental behaviour by PLS (partial least squares) structural equation modelling based on the survey data of 426 respondents in China. The results indicate that recycling efforts have a positive effect on pro-environmental behaviour through the mechanism of feelings of pride and environmental self-identity. We hypothesise that past pro-environmental behaviour is more likely to promote an individual’s environmental self-identity when the behaviour is incurred with a higher costliness. However, the results show that only when individuals autonomously perform costly recycling behaviour, the signalling strength of previous recycling efforts is higher to promote environmental self-identity. On the contrary, the high costliness weakens the signalling strength of previous recycling efforts through producing negative emotions. Our results show that when reminding people of their past pro-environmental behaviour in order to promote future pro-environmental behaviour, it is useful to emphasize the autonomously taken costliness of behaviour as it can strongly signal that one is a pro-environmental person, thus as to strengthen environmental self-identity.

How COVID-19 Could Change the Economics of the Plastic Recycling Sector

The price of oil has a great influence on prices of recycled plastics and, therefore, plastic recycling efforts. Here, we analyze the effects of the ongoing COVID-19 pandemic on crude oil price and how this, in turn, is likely to affect the degree of plastic recycling that takes place. Impulse response functions and variance decompositions, calculated from the structural vector autoregression, suggest that changes in crude oil prices are key drivers of the price of recycled plastics. The findings highlight that because plastics are made from the by-products of oil, falling oil prices increase the cost of recycling. Therefore, the price of recycled plastics should be supported using taxes while encouraging sustained behavioral changes among consumers and producers to selectively collect and recycle personal protective equipment so that they do not clog our landfills or end up in our water bodies as plastic waste.

A devil's bargain

Plastics have become an essential material of the modern global consumer economy, yet many of the properties that make them useful in so many applications also make them a serious environmental threat. As for much new technology, their development and proliferation occurred with little consideration for their impacts, but now it is impossible to deny their dark side as we confront a rapidly growing plastic pollution problem. In this special issue, we examine a range of topics related to plastics, from their distribution in the environment to their development into an evolutionary trap for animals to ways we can rethink them to create a better future. A series of Reviews discusses how plastics are best understood as novel geomaterials, the evolutionary and ecological dimensions of plastic ingestion by wildlife, the accumulation and effects of plastic pollution in the environment, and how innovations in upcycling and recycling may affect the fate of plastics and drive advances in next-generation materials design. Complementing these Reviews, a Policy Forum and a pair of Perspectives discuss efforts to develop a global agreement to combat plastic pollution, provide an overview of the history of environmental bioplastics and their implications, and offer suggestions for designing plastics for a circular bioeconomy. Finally, a brace of News Features explores how enzymes are being used to aid in plastic recycling efforts and how museums are trying to stop plastics in their exhibits from breaking down. The time for preventing plastic pollution is long past—the time for changing the future of plastics in our world, however, is now.

The Study of User Perception Towards Digital Information Design

Social media is increasingly becoming a key platform in disseminating information to the masses. With its free platform and wide audience penetration, various topics are shared across which also includes promoting environmental awareness. However, just like various other topics, any digital information constantly competes for user attention and consumption. The information design strategy put in place must be understood to assess user perception towards the content where a well-designed information will motivate users to like and share content. A study employing Instagram post-type categorization and survey probing user perception was carried out in the context of NGOs championing recycling efforts. The findings show that users prefer visualized information. The results can be used as a guideline for digital information designers to improve the information design technique particularly in the context of creating awareness that could potentially dive into virality element fitting with user perception and preferences.

Characterization and recycling potential of the discarded cathode ray tube monitors

Abundantly available discarded cathode ray tubes are a serious threat to the environment and loss to resource conservation and therefore requiring immediate recycling efforts. In this study, extensive characterization of all parts of the discarded cathode ray tube was carried out using X-ray diffraction, thermo-gravimetric, X-ray photoelectron spectroscopy, Scanning electron microscope, and Energy Dispersive Spectroscopy. The detailed mass balance and the overall potential (market value calculations) of discarded cathode tubes as an urban source, and the techno-economic calculations were carried to provide guidelines for the development of recycling technology. Recycling techniques of cathode-ray tubes were reviewed, and a concise flow sheet for overall recycling was prepared for evaluation and assessment of recycling potential. The thermal response and dissociation kinetics of the phosphor were investigated, and the activation energy in the temperature range (600–930 °C) for thermal processing of phosphor was determined as 105.4 kJ/ mol. Effective recycling of cathode ray tube phosphor can yield 4.5 g of Y, Eu and, La metal values per 500 kg of discarded units with a market value of 835 INR and an overall market value of 115,870 INR ($1567.34). The different fractions of cathode-ray tube glass were recycled using a combination of the pyrometallurgical and hydrometallurgical processes for metal recovery. Recycling of different fractions of hazardous discarded cathode ray tubes is necessary and is beneficial for a circular economy for recovery of phosphor, copper, glass and coating material, plastics, and steel.

Çevresel Tutumların ve Çevresel Davranışların, Çevresel Duyarlılık ve Algılanan Çevresel Riskler ile İlişkisi

The study aims to determine the relationship between students’ environmental attitudes and behaviors, and their environmental sensitivity and perceived environmental risks. The study was conducted with 361 Health School students in the 2018-19 academic years. Data were collected by the Environmental Attitude Scale (EAS), Environmental Behavior Scale (EBS), Environmental Sensitivity Scale (ESS), and Environmental Risk Perception Scale (ERPS). According to Multivariate Linear Regression Analysis: There was a positive association between EAS and the Chemical Waste Risk subscale of the ERPS (p<0.01); and also, between the ESS and subscales of the EBS (p<0.001). Another positive association was found between the Recycling Efforts subscale of the EBS and Chemical Waste Risk subscale of the ERPS and between Resource Depletion subscale of the ERPS and subscales of the EBS (p<0.05). Environmental sensitivity affected environmental behaviors positively but it was not a determinant of environmental attitudes. Some of the perceived environmental risks played an important role in existing environmental behaviors and environmental attitudes.

A Comprehensive Review of the Advancement in Recycling the Anode and Electrolyte from Spent Lithium Ion Batteries

Owing to the increasing pressure on the ecological effect of solid waste disposal and developing the need for disposal of the corresponding hazardous metals, recovery of spent lithium ion batteries (LIBs) has gain worldwide attention in recent years. Much work has been done in this regard in the past few decades, and several new, interesting, and unique methods have been developed to recycle the cathode, anode, and electrolyte. Therefore, time has come to summarize the highlights in this emerging area to facilitate young researchers. In this review, starting from the current market demand and commercial value of lithium ion batteries, we have summarized the most recent progress in the direction of recycling the cathode and anode materials and electrolyte. At the beginning, an overview of the recycling techniques is presented to grasp understanding of the topic. Later, laboratory and industrial investigations and implementation are reviewed with emphasis on anode (graphite) and electrolyte recovery. Life cycle assessment of end-of-life LIB recycling, limitations, and future efforts have also mentioned to focus on improving the efficiency of metal extraction and separation with the sustainable and systematic recycling of spent lithium ion batteries.

Complicated Green Advertising: Understanding the Promotion of Clothing Recycling Efforts

The fashion industry, a major global polluter, has been paying more attention to the environmental and ecological impacts of clothing production. A subset of established brands — some supported by the US group Cotton Incorporated — have pushed programmes where denim and other types of clothing can be turned in at a store, collected, and then sent for recycling. Often, these recycling efforts are supported with promotional offers that allow customers to purchase new items at a discount. This is potentially paradoxical as in this way recycling is used to promote further consumption. This paper interrogates the promotion of recycling programmes from four US brands: American Eagle, H&M, Madewell and The North Face. To do so, this paper uses a textual analysis and deconstruction of the brands’ websites and in-store advertising, as well as a KWIC analysis of Twitter messages. By examining the tangible communication components that support the recycling efforts, this analysis highlights the ‘complicated greenness’ (Hepburn, 2013) within the process as consumer incentives for recycling promote further consumption and often leave consumers confused as to the environmental efficacy of such practices. This paper offers considerations for ways fashion brands might be more impactful in their foray into environmentalism.

A national survey on attitudes and barriers on recycling and environmental sustainability efforts among Canadian anesthesiologists: an opportunity for knowledge translation.

Anesthesia-related activities produce 25% of all operating room (OR) waste and contribute to environmental pollution and climate change. The aim of this study was to document Canadian anesthesiologists' current practice, attitudes towards, and perceived barriers regarding recycling of OR waste and environmental sustainability efforts. With Research Ethics Board approval, members of the Canadian Anesthesiologists' Society (CAS) completed an online survey consisting of 25 questions assessing current environmentally sustainable practices in anesthesiology and gaps, barriers, and interest in gaining further knowledge on this topic. Four hundred and twenty-six of 2,695 (16%) CAS members responded to the questionnaire. Despite a willingness to recycle at work among most anesthesiologists (393/403, 97.5%), only 122/403 (30.2%) did so. Other sustainability efforts in Canadian ORs included donating unused medical equipment and supplies to medical missions (198/400, 49.5%) and evening shut-off of anesthesia machines and other OR equipment (185/400, 46.3%). Reported barriers to recycling in the OR included a lack of support from hospital/OR leadership (254/400, 63.5%) and inadequate information/education (251/400, 62.8%). Only 122/389 (31.4%) of respondents were aware of any efforts to expand sustainability programs at their institutions but 273/395 (69.1%) of respondents indicated an interest in obtaining further education on the topic. Canadian anesthesiologists appear ready to incorporate environmental sustainability in their practice but indicate that significant barriers exist. Our study highlights the need for further educational programs and implementation strategies.

Eco-friendly paving materials using waste PET and reclaimed asphalt pavement

Waste polyethylene terephthalate (PET) and reclaimed asphalt pavement (RAP) represent two categories of waste materials that are currently enduring major recycling efforts around the world. This study proposes a method to incorporate PET-based additives into asphalt mixtures containing RAP. Waste PET was chemically treated using an aminolysis process to synthesise PET-based additives. The effect of the additives on asphalt binder was then characterised through molecular dynamic simulation (MDS) which indicated that the additives increase the intermolecular interaction within the asphalt binder molecules. Subsequently, binders modified with PET additives were used to prepare mixtures containing RAP at various percentages and tested through conventional rheological tests, such as Marshall Stability tests and Indirect Tensile Stiffness Modulus (ITSM) tests. Mixtures with 2% of PET additives and RAP showed improved stability and Marshall quotient values, demonstrating better resistance to permanent deformation. It was also observed that the PET additives have the substantial effect to reduce the ageing effect of mixtures containing RAP, thereby improving the longevity and service life of pavement mixtures. Overall, the results indicated that the usage of such PET derived additives can have a significant positive effect in improving the performance of asphalt mixtures containing RAP.

Optimal Recycling Under Heterogeneous Waste Sources and the Environmental Kuznets Curve

We investigate how the relationship between economic growth and pollution is affected by the source of pollution: production or consumption. We are interested in polluting waste that cannot be naturally absorbed, but for which recycling efforts aim to avoid massive pollution accumulation with harmful consequences in the long run. We distinguish the cases where recycling efforts are capital-improving or capital-neutral. Based on both environmental and social welfare perspectives, we determine how the interaction between growth and polluting waste accumulation is affected by the source of pollution, i.e., either consumption or production, and by the fact that recycling may or may not act as an income generator, i.e., either capital-improving or capital-neutral recycling efforts. Several new results are extracted regarding optimal recycling policy and the Environmental Kuznets Curve. Beside the latter concern, we show both analytically and numerically that the optimal control of waste through recycling allows to reaching larger (resp., lower) consumption and capital stock levels under consumption-based waste compared to production-based waste while the latter permits to reach lower stocks of waste through lower recycling efforts.

Challenges and opportunities in municipal solid waste management in Mozambique: a review in the light of nexus thinking

As one of the least developed countries in the world, Mozambique has many challenges to overcome during its attempts to arrange the country’s solid waste management system. Some of these challenges are unique to the country while many are common to other developing countries in the region as well as elsewhere. One unique challenge to overcome is the adverse impact made by the 16-year long civil war that ended in the 1990’s. Financial difficulties combined with lack of proper planning/coordination has not allowed some waste-related industries to come back to full swing yet. Lack of financial, technical, and trained human resources as well as the inefficiencies in the legal and intuitional arrangements are some of the issues common to many other developing countries. However, some of the challenges can be converted to opportunities relatively easily. Finding ways to capitalize on the high organic fraction of the country’s municipal solid waste (MSW) is one such example. Together with a comprehensive review of the current status of MSW management, this manuscript presents a study conducted on how integrated resources management concepts may help Mozambique to make its MSW management more sustainable. Building on the existing initiatives that support recycling and other resource recovery efforts, as well as capacity and institutional development, this investigation explores how nexus thinking can help to improve the status of solid waste management. It is also interesting to note that this process will in turn help the country to achieve some of the sustainable development goals (SDGs) set by the United Nations. While proper and sustainable MSW management addresses SDG 12 in a comprehensive way, it also helps with achieving other goals such as 3, 6, and 15 to a certain extent.

Challenges and opportunities in municipal solid waste management in Mozambique: a review in the light of nexus thinking

As one of the least developed countries in the world, Mozambique has many challenges to overcome during its attempts to arrange the country’s solid waste management system. Some of these challenges are unique to the country while many are common to other developing countries in the region as well as elsewhere. One unique challenge to overcome is the adverse impact made by the 16-year long civil war that ended in the 1990’s. Financial difficulties combined with lack of proper planning/coordination has not allowed some waste-related industries to come back to full swing yet. Lack of financial, technical, and trained human resources as well as the inefficiencies in the legal and intuitional arrangements are some of the issues common to many other developing countries. However, some of the challenges can be converted to opportunities relatively easily. Finding ways to capitalize on the high organic fraction of the country’s municipal solid waste (MSW) is one such example. Together with a comprehensive review of the current status of MSW management, this manuscript presents a study conducted on how integrated resources management concepts may help Mozambique to make its MSW management more sustainable. Building on the existing initiatives that support recycling and other resource recovery efforts, as well as capacity and institutional development, this investigation explores how nexus thinking can help to improve the status of solid waste management. It is also interesting to note that this process will in turn help the country to achieve some of the sustainable development goals (SDGs) set by the United Nations. While proper and sustainable MSW management addresses SDG 12 in a comprehensive way, it also helps with achieving other goals such as 3, 6, and 15 to a certain extent.

A periodic location routing problem for collaborative recycling

ABSTRACTMotivated by collaborative recycling efforts for non-profit agencies, we study a variant of the periodic location routing problem, in which one decides the set of open depots from the customer set, the capacity of open depots, and the visit frequency to nodes in an effort to design networks for collaborative pickup activities. We formulate this problem, highlighting the challenges introduced by these decisions. We examine the relative difficulty introduced with each decision through exact solutions and a heuristic approach that can incorporate extensions of model constraints and solve larger instances. The work is motivated by a project with a network of hunger relief agencies (e.g., food pantries, soup kitchens and shelters) focusing on collaborative approaches to address their cardboard recycling challenges collectively. We present a case study based on data from the network. In this novel setting, we evaluate collaboration in terms of participation levels and cost impact. These insights can be generalized to other networks of organizations that may consider pooling resources.

Separation of nanoparticles: Filtration and scavenging from waste incineration plants

Increased amounts of nanoparticles are applied in products of everyday life and despite material recycling efforts, at the end of their life cycle they are fed into waste incineration plants. This raises the question on the fate of nanoparticles during incineration. In terms of environmental impact the key question is how well airborne nanoparticles are removed by separation processes on their way to the bag house filters and by the existing filtration process based on pulse-jet cleanable fibrous filter media. Therefore, we investigate the scavenging and the filtration of metal nanoparticles under typical conditions in waste incineration plants. The scavenging process is investigated by a population balance model while the nanoparticle filtration experiments are realized in a filter test rig. The results show that depending on the particle sizes, in some cases nearly 80% of the nanoparticles are scavenged by fly ash particles before they reach the bag house filter. For the filtration step dust cakes with a pressure drop of 500Pa or higher are found to be very effective in preventing nanoparticles from penetrating through the filter. Thus, regeneration of the filter must be undertaken with care in order to guarantee highly efficient collection of particles even in the lower nanometre size regime.